{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "This study aims to explore the effect of selenium in fluoride - induced renal cell apoptosis in rats and determine the optimal level of selenium in drinking water to prevent fluorosis ."}
{"Chemical": ["selenium", "fluoride"]}